The present invention relates generally to a bucket for an excavating machine and more particularly to a corner adapter for mounting a ground engaging tooth to an excavating bucket.
Buckets for excavating machines such as hydraulic excavators, backhoes, wheel loaders and the like include a plurality of ground engaging teeth disposed on a cutting edge. The teeth are evenly spaced between a pair of bucket side walls. Each tooth is removably attached to an adapter, that is in-turn welded to the cutting edge of the bucket. While most teeth and adapters extend perpendicularly outward from the leading edge, some tips positioned at corners of the bucket are arranged to extend outward past the side wall. Having the teeth angled outwardly on the corners loosens material beyond the bucket sides, thus reducing drag.
An example of a tip and adapter that extends at an outward angle past the side wall is in shown in U.S. Pat. No. 5,992,062 to Evans et al. As shown the adapter includes a top strap, a bottom strap and a nose portion. A longitudinal axis is defined on each of the top and bottom straps, the nose portion defines another longitudinal axis. Each of the longitudinal axes are parallel to one and other. The geometry of these corner adapters includes multiple compound angles where the nose portion connects with the top and bottom straps. These compound angles increases cost of tooling and expense associated with manufacturing the adapter. Three different patterns are required to make these castings, a right corner, a left corner and center patterns.
Additionally, the corner adapters shown in Evans et al are positioned into a notch formed into the side wall of the bucket above the base edge. A first weld is provided around the top and bottom straps, fixing the adapter to the base edge, a second weld is provided between the top strap and the notch in the wall. This attachment method complicates the replacement of a worn corner adapter because the welds must be removed using a cutting torch. Removing the second weld often results in excess damage to the side wall. Also the interface between the base edge and side walls undergoes extremely high stress during digging operations.
An additional problem related to corner adapters, is the positioning of the welds used to attach the adapter to the bucket. The welds are typically positioned at unfavorable locations having high stress concentrations, such as where the thickness of the strap is reduced. This increases the potential for failure of the adapter.
The present invention is directed to overcoming one or more of the above mentioned problems.
The present invention provides a corner adapter for use with an implement bucket. The corner adapter is adapted to receive a ground engaging tooth and includes a nose portion having a back end, top surface, a bottom surface and a first longitudinal centerline. A top and bottom strap extend from said back end of the nose portion. The bottom strap includes a top surface, a bottom surface and a pair of side surfaces extending between the top and bottom surfaces. A second longitudinal centerline is defined between the top and bottom surfaces of the bottom strap. The top strap includes a top surface, a bottom surface and an inner side surface and an outer side surface extending between the top and bottom surfaces. A third longitudinal centerline is defined between the inner side surface and the outer side surface, wherein an angle is defined between the first centerline and the third centerline.